The present invention relates to inventory control systems and, more particularly, to controlling the sequence and completeness of selection of items on a repetitive bases.
Particularly in the consumer goods market, but also in other areas of commerce, it is common for the manufacturer to be required to package and ship groups of parts for use in the subsequent assembly of an article. For example, large toys and bicycles are often sold partially assembled and are packaged with the appropriate number and kind of fasteners and parts to allow complete assembly by the purchaser. If, however, the wrong types or numbers of fasteners and smaller parts are supplied or missing, the purchaser is delayed in his or her assembly and must either return the purchased article or request that the additional parts be supplied. This incomplete or erroneous packaging thus causes loss of consumer satisfaction with his or her purchase and ultimately loss of confidence in the ability of the manufacturer to supply a complete package for assembly.
In the past, the difficulty for the manufacturer has been the human error in the manual repetitive selection of items to form the desired group of items. In such a selection process it is common to provide a plurality of bins or other containers each of which holds a plurality of one of the parts to be selected. These bins are usually adjacent one another so as to allow the worker to select the desired parts or items to form the desired group. However, no matter how careful the worker is, it is common to have an occasional error in the selection process and the number of errors depends on the skill and care of the individual worker. Therefore, it is usually necessary to constantly check the groups selected by the workers to ensure that the selection process is being carried out correctly and completely. The quality control process usually involves the random checking of selected groups of items to see if they are complete. However, even this checking results in some missed groups of improperly selected items which eventually get to the consumer.
In addition to random checking, it is known to provide a system for the repetitive selection of items where means are provided for sensing when each item of a desired group of items has been selected from a bin and whether the complete group of items has been selected in the proper sequence. This eliminates any error in the selection of items for the particular group of items intended to be selected. However, this system is "hard wired" and is designed for a specific selection sequence. Therefore, it is necessary to rewire or build a completely new system if the selection sequence is changed in any way. Thus, such a system is inconvenient to adapt to multiple uses and must be built for a specific group of items to be selected.